Typically, fibrous structures used for sanitary tissue products contain two or more fiber furnishes. Such fibrous structures typically contain one furnish comprised of relatively long fibers, i.e. fibers with length-weighted average fiber length exceeding about 2 mm. This furnish is intended as reinforcement or strength generation. Then the fibrous structures further comprise at least one relatively short fibered furnish, i.e. having a fiber length less than about 1 mm. The short fibers improve the softness since they are relatively unbonded. The unbonded fibers allow free ends which impart a velvety smoothness to the structure. See U.S. Pat. No. 4,300,981 to Carstens incorporated herein by reference for a disclosure of such velvety structures.
It is well known to those skilled in the art that the use of the short fibers is limited both in the minimum average fiber length which is permissible as well as the fraction of the total furnishes which can be the short-fibered furnish. This is due to the well known fact that use of shorter and shorter fibers normally causes an increase in the propensity of a tissue paper structure to release lint. While a certain amount of lint level is acceptable, excessive lint can be a major problem in production (dust generation). The users of product can also negatively relate to lint as it causes dust accumulation around the home of leaves pieces of the tissue clinging to the body after use.
This problem with lint is heightened when the tissue paper product is made by the so-called through-air dried (“TAD”) papermaking process. This is because the process of tieing-down loose lint is improved when the tissue paper web is pressed against the surface of a Yankee dryer. In some TAD processes, this pressing is changed from pressing over 100% of the area, typical in non-TAD conventional processes, to less than 50%, more preferably even less than 40% of the surface. While the lint reduction accompanying such limited pressing is surprisingly good, it necessarily suffers relative to conventional web making. Furthermore in some TAD processes, the Yankee dryer has been eliminated completely which obviously totally eliminates this means of strength generation.
Today's art limits the short-fibered furnish used in papermaking processes to greater than about 0.75 mm.
Inventors have now found that, in fibrous tissue structures having lint values greater than about 3.5, surprisingly short fiber length, i.e. from about 0.4 mm to about 1.2 mm fibers, can be used in the production and use of such tissue paper structures offering a softness benefit without a substantial increase in lint values.
No prior art teaches a fibrous structure comprising a short fiber having a length of from about 0.4 mm to about 1.2 mm and a coarseness of from about 3.0 mg/100 m to about 7.5 mg/100 m, wherein the fibrous structure has a lint value of greater than about 3.5.